In the air-conditioning industry, the problems caused by build-up or accumulation of salts and other minerals within the filter pads during the evaporation of the water during the cooling process are well known. In an effort to reduce these problems, it is common practice to bleed to waste a certain proportion of the water flowing through the filter pads. The bleed rate of water is normally adjustable depending on the amount of salts and other minerals in the supply water. The bleed rate also needs to be adjustable to compensate in situations where the evaporation rate is very high. One known "bleed-off" arrangement employs a take-off line on the pressure side of the water pump, such line incorporating a flow restricting clamp for restricting the flow of water therethrough and an adjustable water valve to limit the amount of water leaving the water flow system by way of pipe leading to an overflow hose. Such a system is not considered generally satisfactory, and frequently malfunctions through particles in the water recirculating system reducing the orifice in the bleed valve or blocking it totally. Whilst the orifice of such bleed valves is very small, it inherently must be small to allow a low percentage of water to escape under the influence of the pressure needed to recirculate the water.
It is the main object of the present invention to provide an improved water bleed-off system for an evaporative air cooler which is of extremely simple design, inexpensive and can be readily assembled in the cooler body.
It is a further object of the present invention to provide a water bleed-off system for an evaporative air cooler which is able to vary the amount of water which is required to be bled off.
It is still a further object of the present invention to provide a water bleed-off fitting which can also be used as an overflow for the cooler water tank.
It is still a further object of the present invention to provide an improved water bleed-off system which employs a bleed/funnel overflow fitting which can be readily removed from the base wall or floor of the tank of the cooler body and which, when so removed, enables the water from the tank to be drained for cleaning or maintenance purposes.